I have a few questions on parallel I was hoping you could help with relating to running the same command on multiple servers. I'm running version 20180422.
1) When I run:
parallel --results test.csv echo ::: a b c
I get an error:
Can't use an undefined value as a symbol reference at /usr/bin/parallel line 8906.
Is that the correct way to run it to have output into a csv file? If I run this, it runs successfully:
parallel --results -.csv echo ::: a b c
2) When I run:
parallel --results a --nonall -S $SERVER1,$SERVER2 echo a b c
I noticed that a results directory does not get created. Should it be created in this case?
3) Similarly, this doesn't output anything to the screen:
parallel --results -.csv --nonall -S $SERVER1,$SERVER2 echo a b c
4) What I'm really trying to get at with these questions is I'm currently using parallel-ssh (https://code.google.com/archive/p/parallel-ssh
), but not sure if it's still being maintained. With pssh, I can run the same command on many servers and get back the results of running each command on each server - as an example, I may want to run "yum update" on a bunch of servers.
Is it possible to have the output from parallel be similar to the output that pssh provides? pssh displays each server you ran the command on with a success/failure indicator, and then it also logs all output into files, naming each file with the server name.
See some examples at https://www.cyberciti.biz/cloud-computing/how-to-use-pssh-parallel-ssh-program-on-linux-unix
, but let me know if you'd like me to post some here.
Thank you for your help.